I will give brainliest please help need this asap worth 100 points

Answer:
a. R = 8
b. The number of retweets in the thousands in days.
c. I don't understand c I'm sorry.
d. It means the retweets and time in days are in 23.
e. In the picture below
Step-by-step explanation:
r(t) = 9t - 4
r(4) = 9(4) - 4
divide both sides by 4
R(4) = 9 - 1
r = 8